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I am trying to get a CD4026 IC to reset at 6 for a digital clock project. I have some 3-input AND gate IC's but there doesn't seem to any unique conditions that would work.

I do have some CD4017 and was thinking I could use them to trigger the reset of the CD4026 IC's at their count of 6, then reset together.

Is pin 5 to 15 a short? Maybe i need power on caps too?

Vs = 5V IC on top is the CD4017

enter image description here

BobaJFET
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1 Answers1

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5 and 6 are unique in being the only two outputs where the \$b\$ segment is not lit. The two numbers can then be differentiated based on the \$e\$ segment.

If you have an inverter, then \$\overline{b}\cdot e\$ will tell you when 6 is lit, which can then trigger the reset.

You can also include the \$d\$ segment as an input to your 3-input AND gate for extra resilience against slight delays in the output (prevent glitches when it counts from 4 to 5).

Tom Carpenter
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